1. Field of the Invention
The present invention relates to an osteosynthesis plate, in particular for vertebral osteosynthesis, and in particular a plate intended for the osteosynthesis of cervical vertebrae.
2. Description of the Related Art
An osteosynthesis plate is generally fixed using screws engaged through holes formed in the plate. This type of fixing may, in some cases, involve a risk of the screws coming unscrewed, which leads to the possibility of movement of the bone parts that are supposed to be maintained by the plate. This is particularly the case for an osteosynthesis plate for cervical vertebrae, given that these vertebrae are subject to repeated stress and that the extent to which the screws are supported in these vertebrae is reduced due to the reduced dimensions of these screws.
A number of systems have been conceived making it possible to prevent the back-out of screws from osteosynthesis plates, for example back-plates screwed onto the plate, at least partially covering the screws after their insertion.
The existing systems, however, have the drawback of not simultaneously meeting the following needs:                simplicity of structure and relative ease of production;        reduced production cost;        ease and speed of implementation;        perfect anti-backout action of the screws;        possible reversibility of this anti-backout action, in the case where one or several screws must be removed.        